It's correct and reasonable, but ANOVA looks at square of the effect, so you have to go back to the one-sided t-test. But I view the t-test and ANOVA as different views of the same thing.

It's correct and reasonable, but ANOVA looks at square of the effect, so you have to go back to the one-sided t-test. But with two treatments, the t-test and ANOVA are the same thing; the ANOVA F statistic is just $t^2$.